A communication network may include network elements that route packets through the network. Some network elements may include a distributed architecture, wherein packet processing may be distributed among several subsystems of the network element (e.g., line cards).
Service Operation, Administration, and Management (“Service OAM” or “SOAM”), is defined by IEEE 802.1ag and defines Maintenance Entity Group End Points (MEPs) that reside on a line card. MEPs may include service-aware MEPs (e.g., MEPs attached to a service point or flow point) and service-transparent MEPs (e.g., MEPs that are not placed on a service flow point, but rather at a service aggregation point, such as an interface level). The ITU Y.1731 standard complements IEEE 802.1ag by allowing a MEP to transmit a Ethernet Alarm Indication Suppression (Eth-AIS) messages in a network direction away from where it's peer MEP is located (e.g., in an upstream direction opposite to the direction in which the MEP communicates CCM messages). Such Eth-AIS messages allow for alarms to be suppressed when received by a MEP. In a distributed architecture, certain services, such as Enhanced Internal Sublayer Service (EISS) and Internal Sublayer Service (ISS) defined by IEEE 802.3 for ingress and egress interfaces of a network element may reside on different line cards.
One disadvantage of the traditional transmission of Eth-AIS messages in such architectures is that Eth-AIS messages must traverse the entire switch fabric of the network element in the case of a down (e.g., failed or non-operational) MEP. Such approach leads to inefficient use of the switch fabric, and scalability is defined on a single ingress line card that is generating the Eth-AIS messages, and there may be more services to which Eth-AIS messages are to be distributed than can be supported.